Question: Solve for $x$ : $7\sqrt{x} - 6 = 2\sqrt{x} + 9$
Subtract $2\sqrt{x}$ from both sides: $(7\sqrt{x} - 6) - 2\sqrt{x} = (2\sqrt{x} + 9) - 2\sqrt{x}$ $5\sqrt{x} - 6 = 9$ Add $6$ to both sides: $(5\sqrt{x} - 6) + 6 = 9 + 6$ $5\sqrt{x} = 15$ Divide both sides by $5$ $\frac{5\sqrt{x}}{5} = \frac{15}{5}$ Simplify. $\sqrt{x} = 3$ Square both sides. $\sqrt{x} \cdot \sqrt{x} = 3 \cdot 3$ $x = 9$